A PA32 pilot executed an RNAV approach to an airport where the report weather was below landing minimums. A go around was executed followed by a diversion to nearby airport.

Narrative

ATIS was obtained enroute. 400 Overcast and 4sm visibility were the big numbers. I was also made aware that all but one of the runways were closed. I received a full DUATS briefing but didn't see those closures; although the TAF at the time of the briefing only had the weather going down to 600 Overcast. The only option I had was an approach that goes down to 417 AGL straight in or 497 AGL for the circle to land. I was cleared the RNAV Runway 27 circle to land Runway 2L. One could argue the approach was 'at minimums'. I had it in the back of my mind that rarely are ceiling measurements that accurate and I would probably see the field well enough to land. The ceiling was also reported as ragged by local pilots and I would see it through a light spot. The approach was well flown to the published minimums. The airport was found not in sight at the MAP. The missed approach was initiated and flown as cleared. The flight was diverted. Approach and landing were made at another field without issue. I'm not sure why I elected to fly the approach. I know not reading about the runway closures and not having thought through a plan B & C were factors. Perhaps it was some misplaced loyalty to the company knowing that I should 'give it a try' even though Part 135 regulations do not allow us to fly approaches unless 'weather conditions are at or above the authorized IFR landing minimums for that airport.' I knew I would receive grief from operations if I didn't at least try to get in with the weather being so close. In hindsight; it's my career if I get busted for flying that approach. The company will do little to help me. In the future; I will proceed to the IAF hoping for the weather to improve but if it doesn't I will divert or hold and not begin the approach. Hopefully the company can except that as a good enough try. And yes; read my entire preflight briefing carefully; always.